cellio | daf bit: Chullin 11

The g'mara discusses the principle of "follow the majority" and gives examples: in a town with nine kosher butchers and one non-kosher we presume that meat is kosher; in the Sanhedrin laws were decided by a majority; in a complicated case of levirate marriage (where the purpose of the marriage is to produce a child) we presume that a couple is fertile because most are. Many rabbinic opinions about this principle then follow. Today's daf (but not the discussion) ends with one attributed to R. Kahana: where it is possible to ascertain the facts we must do so; it is only in the case where we cannot do so that we follow the majority. (11a-b)